Gilo Research Articles

Methods for evaluating the physiological potential of scarlet eggplant (Solanum aethiopicum) seeds

The use and efficiency of vigour tests depend on the plant species and the development and / or adjustment of methodology to obtain efficient procedures for evaluating seed physiological potential. The objective of this study was to compare different methods for evaluating the physiological potential of scarlet eggplant seeds (Solanum aethiopicum Scarlet eggplant Group). Six seed lots of the “Morro Grande’ cultivar were submitted to the following tests: germination, first count germination, seedling emergence, controlled deterioration (18, 21 and 24% for 24 and 48 hours at 45°C), accelerated ageing (AA) and saturated salt accelerated ageing (SSAA; NaCl) both at 41 and 45°C for 24, 48 and 72 hours) and electrical conductivity (25 and 50 seeds; 25, 50 and 75 mL of deionised water for 1, 2, 4, 8, 12, 16 and 24 hours of imbibition at 25°C). With the exception of electrical conductivity, results from the first count test and for specific times / temperatures of the other tests, generally showed similar ranking of the lots as seen for seedling emergence. It was concluded that the physiological potential of scarlet eggplant seeds can be evaluated using AA and SSAA for 48 h / 41°C and controlled deterioration at 24% moisture content / 24 h / 45°C, thus classifying the seed lots into different vigour levels.

First report of a tospovirus in a commercial crop of Cape gooseberry in Brazil

Viruses from the genus Tospovirus (family Bunyaviridae) are widespread in the Americas, where the following species have been reported: Tomato chlorotic spot virus (TCSV), Tomato spotted wilt virus (TSWV), Groundnut ringspot virus (GRSV), Chrysanthemum stem necrosis virus (CSNV), Zucchini lethal chlorosis virus (ZLCV), Impatiens necrotic spot virus (INSV), Iris yellow spot virus (IYSV) (Jones, 2005), Alstroemeria necrotic streak virus (ANSV), Melon severe mosaic virus (MeSMV) and Bean necrotic mosaic virus (BeNMV) (Ciuffo et al., 2009; Hassani-Mehraban et al., 2010; Oliveira et al., 2011). This work describes the identification of a virus isolated from a commercial crop of Cape gooseberry (Physalis peruviana) in October 2009 in Santa Maria, State of Rio Grande do Sul, Brazil. The disease was identified in a 5 ha cultivated area, where 100% of the plants were showing symptoms of stunting, mosaic, necrosis and foliar distortion (Fig. 1). Spherical particles measuring 80-100 nm in diameter were observed by electron microscopy, giving the initial evidence that a tospovirus might be involved in the disease. Sap from the infected leaves of five different Cape gooseberry plants were inoculated on healthy indicator plants: Petunia hybrida and Chenopodium amaranticolor reacted with local lesions; Datura stramonium, Solanum gilo, S. lycopersicum, S. nigrum, Physalis angulata, P. floridana and P. peruviana (Fig. 1) displayed systemic symptoms. Host reactions were typical for those caused by tospoviruses and symptoms on Physalis species reproduced those observed in the original samples. Testing by plate trapped-ELISA, a positive reaction was only obtained from all five samples using anti-TCSV antiserum (Embrapa, CNPH, Brazil). Negative ELISA results were obtained using antiserum against four other tospoviruses: Tomato spotted wilt virus, Groundnut ringspot virus, Impatiens necrotic spot virus and Chrysanthemum stem necrosis virus. RT-PCR was performed using primers designed to conserved regions of the tospoviral S RNA (Eiras et al., 2001). This generated 440 bp DNA fragments, whose sequence revealed a high degree of nucleotide identity with TCSV isolates from Argentina (98-99%) and Brazil (93-95%). Alignment of the partial coat protein nucleotide sequences showed that the Physalis TCSV isolate (GenBank Accession No. JQ034525) clustered with other TCSV isolates, sharing a clade with Argentinean isolates (Fig. 2). Cape gooseberry is a fruit crop of great nutritional and economic value, which has gradually gained acceptance in international markets, due to its flavour and medicinal properties. In Brazil, it was introduced as a commercial crop into small farms in southern Brazil (Rufato et al., 2008). To our knowledge, this is the first report of natural occurrence of TCSV in commercial crops of Cape gooseberry. To date the disease is restricted to Rio Grande do Sul State. Further epidemiological studies are necessary for understanding the spread of TCSV into this relatively new introduced crop in Brazil.

PERFIL DO CONSUMIDOR E OSCILAÇÕES DE PREÇOS DE PRODUTOS AGROECOLÓGICOS

The consumption of natural foods has increased significantly all over the world, and the term “organic” has acquired great importance. Thus, this study tried to identify the consumer profile of organic foods in Goiânia, Goiás State, Brazil, in order to find out the main difficulties faced to purchase this kind of product. Prices for organic and conventional foods were also compared. The main problem mentioned by the people questioned about the difficulties for consuming this kind of product was the price factor, followed by its availability. Pumpkin (Curcubita moschata), eggplant (Solanum melongena), beetroot (Beta vulgaris L.), carrot (Daucus carota L.), jiló (Solanum gilo Raddi), and cucumber (Cucumis sativu) were the products that showed the highest percent variation in price (conventional x organic).

Hosting Capacity of Horticultural Plants for Insect Pests in Brazil

Factors such as fertilization, allelochemicals, trichomes, weather, and natural enemies can influence pest populations. Thus, it is necessary to understand the factors that predispose vegetable species to pests and the role of polyculture, crop rotation, and neighboring plants. The objective of this research was to study the hosting capacity for pests of Abelmoschus esculentus (L.), Brassica oleracea L. vars. acephala and capitata, Capsicum annuum L., Cucurbita moschata (Duchesne), Cucurbita maxima Duchesne and Cucumis sativus L., Lycopersicon esculentum Mill., Solanum gilo Raddi and Solanum melongena L., and Phaseolus vulgaris L. The higher density of Bemisia tabaci (Genn.) adults on C. sativus can be due to the higher amount of pentacosane and octacosane in this plant. The occurrence of Brevicoryne brassicae (L.) only in Brassica spp. can be accounted for by the nonacosane of these plants. The low trichome density and greater palmitic acid level can explain the greatest damage by Aphis gossypii Glover in A. esculentum. Empoasca sp. was more frequent in P. vulgaris followed by A. esculentum, which are plants with lower K content. Solanum melongena was attacked more by Hydrangea similis (Walker) and Epitrix sp. perhaps because of higher palmitic acid and 11,14,17-eicosatrienoic methyl ester concentrations in their leaves. Frankliniella sp. exhibited more damage in C. sativus probably owing to higher pentacosane and octacosane in its leaves. Sistena sp. was more frequent in C. maxima and had higher octadecane levels and trichome density. The presence of ??-humulene and hexacosane can explain the damage by Tuta absoluta (Meyrick) on L. esculentum.

Gama de hospedeiros e reação de genótipos de tomateiro a Pseudomonas cichorii

Em 2005, foi constatada em dois campos comerciais de tomate no Estado de São Paulo, a ocorrência da queima bacteriana, causada por Pseudomonas cichorii. Em vista disso, foram desenvolvidos estudos visando a determinação da gama de hospedeiros de isolados de Pseudomonas cichorii (IBSBF 2309 e IBSBF 2323), obtidos de tomateiro, provenientes de campos comerciais localizados nos municípios de Bragança Paulista e Mogi Guaçú, SP. Plantas de abobrinha, alface, beldroega, berinjela, beterraba, cenoura, couvebrócolo, datura, fumo, girassol, jiló, melão, pepino, petúnia, pimentão, rabanete, repolho, rúcula, salsa e tomateiro foram inoculadas por pulverização, separadamente, com os dois isolados de P. cichorii de tomateiro e um isolado de girassol (GIR-1). Os isolados IBSBF 2309 e IBSBF 2323 foram patogênicos à beldroega, datura, girassol, pimentão e tomate; GIR-1 foi patogênico apenas à beldroega, datura e girassol, não sendo patogênico ao pimentão e ao tomateiro. No Brasil não se conhecem fontes de resistência dentro do gênero Lycopersicon ou a reação de cultivares de tomateiros a esta bactéria. Vinte e oito genótipos de tomateiro provenientes do Banco de Germoplasma da empresa Sakata Seed Sudamerica Ltda., foram avaliados quanto a reação aos isolados IBSBF 2309 e IBSBF 2323 de P. cichorii, pelo método de inoculação nas folhas. Os maiores níveis de resistência foram observados em AF 11768, AF 2521, AF 11766, AF 11772, AF 229, AF 5719-1 e AF 8162. O genótipo AF 5719-1, que possui o gene Pto, que confere resistência a P. syringae pv. tomato, apresentou um bom nível de resistência a P. cichorii. A identificação de genótipos que apresentem bons níveis de resistência a este patógeno é importante para utilização em programas de melhoramento genético do tomateiro, visando a incorporação de genes de resistência a P. cichorii.

Intake, growth and carcass yield of indigenous goats fed market wastes of sweet potato (Ipomoea batatas) vines and scarlet eggplant (Solanum aethiopicum)

Intake, growth and carcass yield of indigenous goats fed basal diets of market wastes of sweet potato (Ipomoea batatas) vines (SPV) and scarlet eggplant (Solanum aethiopicum) (SEP) were examined in two experiments. In experiment I, the effect of presentation method (chopping, hanging or adding molasses) on the intake of SEP and SPV was evaluated. Presentation method did not influence the intake of SPV while hanging resulted in the highest (P < 0.05) intake of SEP. In experiment II, 24 male growing goats were supplemented with a concentrate (25% cottonseed cake +75% maize bran) in four dietary groups: SEPD, SPVD, SEP+SPV and Control where elephant grass (Pennisetum purpureum) was offered as the roughage. SEP were offered by hanging, while SPV were chopped. The goats were slaughtered after 12 weeks of feeding. Goats in the SEPD group constantly lost weight, hence were not followed to the end. Average daily gain and hot carcass weight were highest (P < 0.05) in the SPVD group (44 g/d and 8.4 kg, respectively), but similar between the SEP+SPV (19 and 6.8) and Control (21 and 6.9) groups. In conclusion, SPV can support goat meat production where standard feed resources are scarce when fed with an energy-protein concentrate. SEP are poorly consumed by goats, hence cannot be used as their sole basal feed.

A Comparative Assessment of the Proximate Composition, Ascorbic Acid and Heavy Metal Content of Two Species of Garden Egg (Solanum gilo and Solanum aubergine)

The proximate composition ,ascorbic acid and Heavy metal contents of two species of Garden egg, Solanum gilo and Solanum aubergine were evaluated using chemical analysis. The result of the proximate composition analysis showed that solanum gilo fruits had the following composition:moisture (74.80%), carbohydrate (52.13%), crude protein (14.87%), crude fibre (16%), crude fat (7%) and ash (10%). It also contained (93.7%) of ascorbic acid. The Solanum aubergine fruits on the other hand contained moisture (94.6%), carbohydrate (58.5%), crude protein (15.75%), crude fat (4%), crude fibre (11.75%) and ash (10%). It also contained (75.9%) ascorbic acid. The Heavy metal concentrations of Solanum gilo fruits are Zn (3.81ppm), Cr (1.74ppm), Cd (0.16ppm), Cu (1.48ppm), Co (0.12ppm) and Hg (0.01ppm). The solanum aubergine fruits on the other hand contained Zn (1.58ppm), Cr (2.45ppm), Cd (0.77ppm), Cu (0.04ppm), Co (0.10ppm) and Hg (0.01ppm). The concentrations of As and Pb in the fruits of both species were not detected. The result Shows that the values of moisture, ascorbic acid, crude fibre and crude fat were higher in S. gilo fruits, while the values of carbohydrate and crude protein were higher in S. aubergine fruits. The result also showed that the fruits of both species have same ash content. The result revealed that the concentrations of Zn, Cu and Co were higher in S. gilo fruits, while S. aubergine fruits has higher values of Cr and Cd. The results also revealed that the concentrations of Cr and Cd in both species of the plant were all above WHO permissible limits of 0.05ppm and 0.005ppm, respectively.

Nuclear and non-nuclear interactions in F_1 hybrid populations of three Solanum species in the subgenus Leptostemonum,section Melongena (Solanaceae)

Reciprocal crosses involving Solanum gilo Raddi, S. anguivi Lam. and S. macrocarpon L., subg. Leptostemonum (Dunal) Bitter sect. Melongena Dunal were produced in order to assess inherent nuclear and non-nuclear influences on hybrid fitness, the extent of genomic change, and species compatibility. Hybrids expressed intermediacy and overlaps in leaf, petiole, petal, and plant height dimensions. Maternal influence was dominant in growth habit, leaf shape and texture, flower colour, and fruit size, while paternal control was limited to fruit colour in Solanum gilo × S. macrocarpon. Pollen viability was reduced from 97.3%-86.5% in parents to 53.8%-20.5% in hybrids. S. gilo × S. macrocarpon produced single-flowered inflorescence, whereas the reciprocal S. macrocarpon × S. gilo developed the ability to perennate, indicating the heterogeneity of the parental genome. Fruits of the hybrids were intermediate or smaller, and had fewer seeds. They were wrinkled in S. gilo × S. macrocarpon, with many aborted seeds. Meiosis was irregular, with few laggards, and isolated uni- and bivalent chromosomes associated with foreign genes in the parent species. Conversely, multivalent and chromosome clumps revealed the extent of homogenization of the parental genomes and species affinity. The maternal genome exerted profound influence on hybrid phenotype and fitness, and should inform and direct future hybridization efforts.

Performance of growing indigenous goats fed diets based on urban market crop wastes

The effect of feeding diets including market crop wastes (sweet potato vines (Ipomoea batatas) and scarlet eggplant (Solanum aethiopicum)) on growth and digestibility was studied using 32 indigenous intact growing male goats. Adding elephant grass (Pennisetum purpureum), maize bran and Leucaena leucocephala leaves, four isocaloric and isonitrogenous diets (Sweet potato vines, Solanum, Mixed and Control) were formulated. After the growth trial, 12 goats were randomly selected for a digestibility trial with the same diets, and 8 goats for a feed preference test comparing the market wastes and elephant grass. Crude protein (CP) intake was highest (P<0.05) for the Control (48 g/day) and lowest for the Sweet potato vines diet (23 g/day). Average daily gain was between 11.0 and 14.2 g/day, and similar between diets. The DM and CP digestibilities of the diets were 0.56 and 0.56 (Control), 0.62 and 0.56 (Mixed), 0.59 and 0.49 (Sweet potato vines), and 0.54 and 0.45 (Solanum), respectively. Faecal and urinary N excretions were highest in goats fed the Sweet potato vines and Solanum diets. Eggplant wastes were the least (P<0.05) preferred. On average the goats spent 5% of their 8-hour time eating eggplant wastes, 34% on sweet potato vines and 36% on elephant grass. Growth performance and N retention were low due to the low intake of feed, especially eggplant wastes.

Desempenho de cultivares de jiló em casa de vegetação

O experimento foi instalado em vasos plásticos, em casa de vegetação em Campinas (SP). Duas cultivares comerciais de jiló - Solanum gilo Raddi - (Comprido Verde-Claro e Esmeralda) e duas introduzidas pelo IAC (Bernacci e Cardoso) foram avaliadas em relação ao desenvolvimento vegetativo e à produtividade. As mudas foram produzidas em bandejas de poliestireno com 128 células e, o transplantio foi realizado aos 40 dias após a semeadura quando estavam no estádio de quatro a cinco folhas definitivas. Aos 30, 60 e 90 dias após o transplantio, avaliaram-se o número de folhas, a altura, a área foliar e as biomassas fresca e seca da parte aérea. Após o início da frutificação, semanalmente, foram colhidos os frutos e avaliaram-se diâmetros, comprimentos e biomassa fresca. As cultivares de jiló Esmeralda e Comprido Verde-Claro produziram frutos mais precoces em relação às cultivares Bernacci e Cardoso. Estas últimas produziram frutos por período mais prolongado. O jiló 'Cardoso' foi o mais produtivo quanto ao número total de frutos e à biomassa fresca total. As cultivares Bernacci e Cardoso da coleção do IAC, com potencial para o melhoramento genético, podem ainda ser utilizadas no sistema de produção de subsistência ou na agricultura familiar que são os sistemas tradicionais de cultivo de jiló.

OPEN FIELD HOST SPECIFICITY TESTS IN BRAZIL FOR RISK ASSESSMENT OF METRIONA ELATIOR (COLEOPTERA: CHRYSOMELIDAE), A POTENTIAL BIOLOGICAL CONTROL AGENT OF SOLANUM VIARUM (SOLANACEAE) IN FLORIDA

Open field experiments were conducted in Brazil to assess the suitability of the South American leaf feeding beetle Metriona elatior Klug for biological control of tropical soda apple, Solanum viarum Dunal in the USA. A multiple choice open field test with eggplant (Solanum melongena L.), bell-pepper (Capsicum annuum L.), potato (Solanum tuberosum L.), tomato (Lycopersicon esculentum Mill.), giló (Solanum gilo Raddi), falsa-jurubeba (Solanum fastigiatum Willd.), and the target weed Solanum viarum, was conducted at the Universidade Federal do Paraná Experimental Station in Curitiba. A second multiple choice-test was conducted 2 years later at the same location excluding the target weed and exposing M. elatior adults to S. melongena, S. tuberosum, L. scullentum, and C. annuum. An S. viarum control plot was established 60 km from the choice-test field. In total, 276 teneral adult beetles were released in the first multiple choice-test. In the second test, 176 beetles were released in the choice-test plot that excluded S. viarum, and 172 adult beetles were released in the S. viarum control plot at different developmental stages of the tested plants. All the plants in each plot were visually checked once a week and the number of adults, immatures, and eggs recorded. Results in the first multiple choice-test showed a complete rejection of the crop plants by M. elatior. Minor feeding (<3%) was observed on eggplant in the second experiment in which S. viarum was excluded from the crop plots, but all M. elatior larvae died in less than a week. The tests were ended when the plants started to senesce. The results of these open field tests corroborate previous quarantine/laboratory host specificity tests indicating that host range expansion of M. elatior to include the solanaceous crops tested is highly unlikely. A petition to release M. elatior in the USA was submitted to the TAG committee in September 2006.

Construção e aplicação de biossensores usando diferentes procedimentos de imobilização da peroxidase de vegetal em matriz de quitosana

Biosensors were developed by immobilization of gilo (Solanum gilo) enzymatic extract on chitosan biopolymers using three different procedures: glutaraldehyde, carbodiimide/glutaraldehyde and epichlorohydrin/glutaraldehyde. The best biosensor performance was obtained after the immobilization of peroxidase on chitosan with epichlorohydrin/glutaraldehyde. Linear analytical curves for hydroquinone concentrations from 2.5x10-4 to 4.5x10-3 mol L-1 with a detection limit of 2.0x10-6 mol L-1 and recovery of hydroquinone ranging from 95.1 to 105% were obtained. The relative standard deviation was < 1.0 % for a solution of 3.0x10-4 mol L-1 hydroquinone and 2.0x10-3 mol L-1 hydrogen peroxide in 0.1 mol L-1 phosphate buffer solution at pH 7.0 (n=8). The lifetime of this biosensor was 6 months (at least 300 determinations).

(31) Growth Response and Fruit Yield of Solanum integrifolium to Growing Medium and Fertility under Reduced Irradiance and Long-day Photoperiod

Four-week-old seedlings of Scarlet eggplant (Solanum integrifolium Poir.), a short-day fruiting vegetable, were grown for 20 weeks in a greenhouse (G/H) from 14 Mar. to 2 Aug. 2005. Mean daily photosynthetic photon flux in the G/H was about 480, 349 and 71 μmol·m–2·s–1 above-, within canopy; and at pot level, respectively in July. Seedlings were grown either in Turface® (fritted clay) or fine sand. Fertilizer treatment consisted of 5 g Osmocote® (18% N-6% P2O5-12% K2O) per pot, plus 100 mL of Peat-lite® (15% N-16% P2O5-17% K2O) solution at 200 mg·L-1 of N twice weekly, or Peat-lite only. Seedling growth (plant height, leaf number) during the first 12 weeks in both growing media was similar regardless of fertilizer treatment. The number of lateral shoots (not fruit number, FRN) increased from early fruit set (week 14) until termination (week 20), but there were no significant (P = 0.05) growing media or fertilizer treatment effects. While root dry mass was similar in both growing media, shoot dry mass was significantly (P &lt; 0.0001) increased in fritted clay. Conversely, FRN and fruit dry mass (FDM) were, respectively, 8- and 11-fold greater in sand compared with fritted clay. Fertilizer treatment had no significant (P = 0.05) effect on both FRN and FDM either in fritted clay or sand. These trends indicate that S. integrifolium can produce limited amounts of fruit under the long daylength conditions of the summer at reduced irradiance, but factors determining shoot growth may have significant influence on fruit yield under this condition.

Development of a biosensor based on gilo peroxidase immobilized on chitosan chemically crosslinked with epichlorohydrin for determination of rutin

A new reagentless biosensor for the square-wave voltammetric determination of rutin in pharmaceutical formulations was developed by immobilization of gilo ( Solanum gilo) crude extract in chitosan matrix. The gilo tissue acts as a source of peroxidase. The highest biosensor performance was obtained after immobilization of the peroxidase in chemically crosslinked chitosan with epichlorohydrin and glutaraldehyde that was incorporated in a carbon paste electrode. In the presence of hydrogen peroxide this enzyme catalyses the oxidation of rutin to quinone and the electrochemical reduction of the product was obtained at a fixed potential of +124 mV versus Ag/AgCl (3.0 M KCl). The performance and factors influencing the resulting biosensor were studied in detail. The bioelectrode exhibited a linear response for rutin concentrations from 3.4 × 10 −7 to 7.2 × 10 −6 M ( r = 0.9998) and the recovery of rutin from the samples ranged from 96.2 to 102.4%. The detection and quantification limits were 2.0 × 10 −8 and 6.3 × 10 −8 M, respectively. The relative standard deviation was less than 1.0% for solutions containing 3.4 × 10 −7 to 7.2 × 10 −6 M rutin in 0.1 M phosphate buffer solution at pH 7.0 ( n = 10). The lifetime of this biosensor was 8 months (at least 500 determinations).

Immobilization procedures for the development of a biosensor for determination of hydroquinone using chitosan and gilo ( Solanum gilo)

A novel reagentless biosensor for the square wave voltammetric determination of hydroquinone was developed by immobilization of gilo ( Solanum gilo) crude extract in the chitosan biopolymer. The gilo tissue was obtained as a source of peroxidase and immobilized on a chitosan matrix using four different methods: physical adsorption, carbodiimide, glutaraldehyde and carbodiimide/glutaraldehyde. The highest biosensor performance was obtained after the immobilization of peroxidase in chitosan by activation of hydroxyl groups with carbodiimide and cross-linking with glutaraldehyde, which was incorporated in a carbon paste electrode. In the presence of hydrogen peroxide this enzyme catalyses the oxidation of hydroquinone to quinone and the silver/silver chloride (3.0 M KCl). The recovery of hydroquinone from the samples ranged from 95.0 to 105% and a rectilinear analytical curve for hydroquinone concentration from 0.25 to 5.5 mM ( r = 0.9996) was obtained. The detection limit was 0.002 mM and the relative standard deviation was lower than 1.0% for 0.3 mM hydroquinone in 0.1 M phosphate buffer solution at pH 7.0 ( n = 8). The lifetime of this biosensor was 6 months (at least 300 determinations).

New hosts of Oidiopsis haplophylli in the solanaceae family in Brazil

A powdery mildew disease was observed on leaves of Solanum gilo, S. melongena, S. tuberosum S. chacoense, Nicotiana rustica and N. tabacum in Brasília (Federal District), Brazil. Symptoms were mainly characterized by adaxial yellow areas in the leaves corresponding to white fungal colonies on the abaxial surface. Profuse sporulation was often observed. Light microscopy of the fungal colonies revealed the presence of conidiophores emerging through stomata with some having two or three branches. Ellipsoidal, subhyaline conidia were predominantly born singly and terminally on the conidiophore. All morphometrical characteristics agreed with those of Oidiopsis haplophylli (Syn. O. sicula). The teleomorph (Leveillula taurica) was not observed. Inoculation tests indicated that O. haplophylli isolates obtained from S. gilo, S. melongena, S. tuberosum, S. chacoense, Nicotiana rustica and N. tabacum were also pathogenic to sweet pepper (Capsicum annuum) and tomato (Lycopersicon esculentum). This is apparently the first report of these Solanaceae species as hosts of O. haplophylli in Brazil. This disease may become important in these crops, especially in greenhouses, and in hot and dry areas where drip irrigation is employed.

Yield of scarlet eggplant ( Solanum aethiopicum L.) as influenced by planting date of companion cowpea

Growth and fruit yield of scarlet eggplant were examined under intercropping with an erect and semi-spreading early maturing cultivars of cowpea in an additive intercropping model with scarlet eggplant as the main crop, in two dry seasons, under irrigation. Cowpea was planted simultaneously with scarlet eggplant, 2 and 4 weeks ahead of scarlet eggplant. Land equivalent ratio (LER) of the intercrops ranged from 1.38 to 1.94, indicating that the intercrops were more productive than the pure crops. Reduction in fruit yield of the main crop, when intercropped with the semi-spreading cowpea cultivar was significantly ( p < 0.01) greater than with the erect cowpea cultivar. Simultaneous planting of cowpea and scarlet eggplant produced 90–99% the fruit yield of sole scarlet eggplant, while planting cowpea 2 and 4 weeks ahead produced 65–80% and 58–60% of sole crop yield, respectively. Competition between component crops was however most favourable for both cultivars of cowpea when planted 2 weeks ahead of scarlet eggplant. Planting cowpea 2 weeks ahead of the main crop also produced the highest LER most likely due to more efficient utilization of sunlight, water and soil nutrients. Simultaneously planting cowpea and transplanting scarlet eggplant, is recommended for such additive intercropping system, aimed at full yield of scarlet eggplant with additional cowpea for food, income or fodder.

Morphological and Molecular Variation in a Collection of Eggplants from a Secondary Center of Diversity: Implications for Conservation and Breeding

Eggplant (Solanum melongena L.) was introduced by the Arabs into Spain. Since then, many local cultivars have arisen. These materials are grouped in four cultivar groups: “round,” “semi-long,” “long,” and “listada de Gandía.” We studied the morphological and molecular [amplified fragment length polymorphism (AFLP)] diversity of a collection of 28 Spanish traditional cultivars of eggplant. Four eggplant accessions from different origins were used as controls and three scarlet eggplant (Solanum aethiopicum L.) accessions as outgroups. Morphology and AFLP markers showed that S. melongena and S. aethiopicum are separate taxonomic entities, and that, compared to controls, Spanish eggplants are very variable, indicating that the Iberian Peninsula can be regarded as a secondary center of diversity. Morphological differences were found among cultivar groups in traits other than those used for the grouping although, in some cases, accessions from different cultivar groups shared a similar general morphology. Eggplant cultivar groups also showed some genetic differences, which are revealed in the gene diversity statistics (GST = 0.30). Nonetheless, no individual AFLP markers specific and universal to one cultivar group could be found. “Round” cultivars were genetically more diverse than the other cultivar groups. A positive correlation (r = 0.68) was found between morphological and molecular distances. However, correlations between geographical and either morphological or molecular distances were low. Results suggest that evolution of eggplants in Spain has involved frequent hybridizations and a frequent movement and exchange of seeds. Structure of diversity among regions indicates that most of the diversity can be collected in single selected regions. All these results have important implications in eggplant germplasm conservation and breeding.

Hypolipidaemic Potentials of Solanum melongena and Solanum gilo on Hypercholesterolemic Rabbits

The fresh, ripe fruits of Solanum melongena and Solanum gilo were investigated for their possible hypolidemic potentials in hypercholesterolemia induced in New Zealand white rabbits by feeding the animals with normal diet supplemented with 1% cholesterol and groundnut oil for 3 weeks. Hypercholesterolemic rabbits were thereafter treated with normal diet supplemented with 10% of each fruit for 6 weeks. Rabbits fed with normal diet and hypercholesterolemic diets through out the experiment were used as negative and positive controls respectively. There was a significant increase in the weight of hypercholesterolemic rabbits, both test (Groups D and E) and control (Groups B and C) (P<0.01) compared with normal control (Group A). It was observed that the hypercholesterolemic rabbits treated with normal diet elicited a significant reduction in fasting serum cholesterol (11.52%), triglyceride (16.5%) and LDL cholesterol (41.13%) but a significant increase in HDL cholesterol (16.48%) and also in the HDL/LDL ratio (1.10), four weeks after replacement of high cholesterol diet with normal diet. This positive response was however more pronounced in fruit s treated rabbits. Solanum melongena and Solanum gilo significantly reduced serum total cholesterol by 65.40 and 52.69% respectively, triglyceride by 47.7 and 27%, LDL cholesterol by 85 and 83% respectively. They also increased significantly serum HDL by 24.7 and 25% respectively leading to increased HDL/LDL cholesterol ratio (3.37 and 3.25 respectively). This trend was also similar with liver lipid levels. Histopathological examination of the liver and aorta paraffin section stained with Haematoxylin and Eosine showed fewer lesions in the hypercholesterolemic rabbits treated with Solanum fruits compared with control hypercholesterolemic rabbits. These observations demonstrated that Solanum melongena and Solanum gilo have strong hypolipedemic effect which combined with improved HDL/LDL ratio is an indication of the possible use of this fruit in the treatment of diseases associated with hyperlipidemia such as ishcaemi c heart diseases and arteriosclerosis.

Resistance to Leveillula taurica in the genus Capsicum

One hundred and sixty‐two Capsicum genotypes were evaluated for powdery mildew (Leveillula taurica) resistance, following inoculations with a suspension of 5 × 104 conidia mL−1 on 10‐leaved to 12‐leaved plants. Genotypes were graded into five resistance classes, based on the areas under the disease progress curves calculated from disease incidence (percentage infected leaves per plant) and severity (total number of colonies per plant). Results revealed a continuum from resistance to susceptibility, with the majority (70%) of C. annuum materials being classified as moderately to highly susceptible to L. taurica. Conversely, C. baccatum, C. chinense and C. frutescens were most often resistant, indicating that resistance to L. taurica among Capsicum species is found mainly outside the C. annuum taxon. Nevertheless, some resistant C. annuum material was identified that may be useful for resistance breeding. Eight genotypes were identified as immune to the pathogen: H‐V‐12 and 4638 (previously reported), and CNPH 36, 38, 50, 52, 279 and 288. Only H‐V‐12 and 4638 are C. annuum, while all others belong to the C. baccatum taxon. Latent period of disease on a set of commercial sweet pepper genotypes varied, indicating diverse levels of polygenic resistance. The latent period progressively reduced with plant maturity, from 14·3 days in plants at the mid‐vegetative stage to 8·6 days in plants at the fruiting stage. Young plants of all commercial genotypes tested at the early vegetative stage were immune, irrespective of the reaction of the genotype at later stages, demonstrating widespread juvenile resistance to L. taurica in the Capsicum germplasm. Inoculation of plants of different botanical taxa with a local isolate indicated a wide host range. Some hosts, including tomato (Lycopersicon esculentum), artichoke (Cynara scolymus) and poinsettia (Euphorbia pulcherrima), produced large amounts of secondary inoculum. Other hosts included okra (Abelmoschus esculentus), eggplant (Solanum melongena), cucumber (Cucumis sativus), Solanum gilo, Chenopodium ambrosioides and Nicandra physaloides.